نتایج جستجو برای: thiourea
تعداد نتایج: 2681 فیلتر نتایج به سال:
An efficient synthesis of novel 4-(2-phenyl-1,2,3-triazol-4-yl)-3,4-dihydro-pyrimidin-2(1H)-(thio)ones from 1,3-dicarbonyl compounds, 2-phenyl-1,2,3-triazole-4-carbaldehyde and urea or thiourea under ultrasound irradiation and using samarium perchlorate as catalyst is described. Compared with conventional methods, the main advantages of the present methodology are milder conditions, shorter rea...
Thiourea (TU)/amine base cocatalysts are commonly employed for well-controlled, highly active "living" organocatalytic ring-opening polymerizations (ROPs) of cyclic esters and carbonates. In this work, several of the most active cocatalyst pairs are shown by 1H NMR binding studies to be highly associated in solution, dominating all other known noncovalent catalyst/reagent interactions during RO...
Reaction of the potassium salt of N-thiophosphorylated thiourea 2-PyNHC(S)NHP(S)(OiPr)(2) (HL) with PdCl(2) in aqueous MeOH leads to the formation of two mononuclear homoleptic complexes [Pd{2-PyNHC(S)NP(S)(OiPr)(2)-1,5-S,S'}(2)] ([Pd(L-1,5-S,S')(2)]) and [Pd{2-PyNHC(S)NP(S)(OiPr)(2)-1,5,7-N,N',S}(2)] ([Pd(L-1,5,7-N,N',S)(2)]), while the mechanically induced solid-state reaction of KL and PdCl(...
We have developed a liquid-phase route for combinatorial synthesis of novel substituted 5-(1,2,4-oxadiazol-5-yl)-3,4-dihydropyrimidine-2(1H)-thiones. Biginelli-type three-component condensation of 1-(3-aryl-1,2,4-oxadiazol-5-yl)acetones, thiourea, and benzaldehydes is shown to result in new 5-(1,2,4-oxadiazol-5-yl)-3,4-dihydropyrimidine-2(1H)-thione heterocyclic system. If salicylaldehydes are ...
Precise spatio-temporal organization of chemical, hydrodynamic, and mechanical processes is typical for biological systems where particular chemical reactions have to accrue in precisely assignment place and time. It is rarely studied and observed in chemical systems. We report unusual precipitation pattern formation of PbSO(4) in chemical media (Pb(2+)-Chlorite-Thiourea System). We have found ...
An attempt has been made to assess the validity of applying the frictional and viscous coefficients of bulk water to the movement of water and solutes through the urinary bladder of the toad. The temperature dependence of diffusion of THO, C(14)-urea, C(14)-thiourea, and net water transfer across the bladder was determined in the presence and absence of vasopressin. The activation energy for di...
B13, a ceramide analogue, is a ceramidase inhibitor and induces apoptosis to give potent anticancer activity. A series of thiourea B13 analogues was evaluated for their in vitro cytotoxic activities against human renal cancer Caki-2 and leukemic cancer HL-60 in the MTT assay. Some compounds (12, 15, and 16) showed stronger cytotoxicity than B13 and C6-ceramide against both tumor cell lines, and...
Tris(3-aminopropyl)amine-based tripodal urea and thiourea receptors, tris([(4-cyanophenyl)amino]propyl)urea (L1) and tris([(4-cyanophenyl)amino]propyl)thiourea (L2), have been synthesized and their anion binding properties have been investigated for halides and oxoanions. As investigated by 1H NMR titrations, each receptor binds an anion with a 1:1 stoichiometry via hydrogen-bonding interaction...
Measurements have been made of the permeability of the isolated urinary bladder of the toad to a number of small solute molecules, in the presence and absence of vasopressin. Vasopressin has a strikingly specific effect on increasing permeability of the bladder to a group of small, uncharged amides and alcohols while penetration by other small molecules and ions is unaffected. The movement of u...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید